Bristol Jupiter

The Bristol Jupiter is an air cooled 9-cylinder aircraft engine. The radial engine was developed shortly before the end of the First World War by Roy Fedden at the Cosmos Engineering Company. From 1918 to 1935, 7100 engines were built and used in a large number of aircraft.

The Jupiter engine was a big commercial success and was considered one of the most reliable aircraft engines at all. In the 1920s and 1930s the type was still further improved and in 1927 came variants with mechanical charging for use, was the last version of the Jupiter XF.

Due to budget cuts in military spending after the war ended in 1920 Cosmos Engineering Co. was insolvent. The Bristol Aeroplane Co. Ltd.. bought the company, including all patents for 15,000 pounds sterling and the team of chief engineer Roy Fedden developed the engine with the at that time with radial engines unusual four-valve technology ( four valves per cylinder) on. The cylinders were machined from forgings. The cylinder heads were first produced as cast steel, but later manufactured from an aluminum alloy. From 1927 forged cylinder heads were used.

The engine was used in a number of civil aircraft. Militarily, it was at the Bristol Bulldog, Gloster Gamecock and the use of the Boulton -Paul Side beach. In addition, there was an extremely coveted engine, when it came to the drive of prototypes

There were a number of licensing. Total licenses were sold in 14 states. Best known are the engines manufactured in France as Gnôme -Rhône Jupiter 9 and in the USSR as M- 22, which were used among others in the Polikarpov I-16. In Germany in 1929 Siemens & Halske acquired a license to build the engine, but not for the Bristol- original, but the Gnôme Rhône - 9, which went as Siemens Sh 20/Sh 21 in production. The aircraft, which were equipped with it, were, for example, the Focke -Wulf A 38 " Seagull", the twin-engine Dornier Wal, the four-engined Dornier Do R " Superwal " and initially also the Dornier Do X. The built from 1930 successor Sh 22 ( Bramo = 322) was further developed to Bramo 323 and built until 1944. In Japan, the Nakajima -Werke in 1924 bought a license.

Fedden began in 1925 with the development of a successor. With shorter stroke and therefore less displacement, but with charging, also neunzylindrige Bristol Mercury was completed in 1927. The Jupiter supercharged 1931 received the designation Bristol Pegasus. Bristol built the types Mercury and Pegasus to 1944; the Jupiter - production ended in 1935 with the appearance of more powerful turbocharged engines.

Specifications

  • Engine type: air-cooled 9-cylinder radial engine with and without propeller gearbox (Jupiter VII with charger)
  • Bore: 5.75 inches (146 mm)
  • Stroke: 7.5 inches ( 190.5 mm); Mercury: 6.5 inches ( 165 mm)
  • Displacement: 28.7 liters ( 24.9 l Mercury )
  • Weight: 330 kg (Jupiter XFA with loader 451 kg); Mercury: 438 kg
  • Gas exchange: OHV, 4 valves
  • Continuous power: 442 hp at 1575 min-1
  • Start Power: 585 hp at 1950 min-1
  • Compression ratio: 5.3:1
Bore (engine) Engine displacement List of aircraft engines
78091
de